The long-standing debate about the way in which the universe is expanding focuses on two possibilities.

The first is that the universe is homogenous and isotropic - so is entirely the same in all directions. And the second is that it is anisotropic, meaning it can look uniform from the outside but there is actually a preferred direction built in.

In the early 2000’s, there were some hints that anisotropy might be the case when NASA’s Wilkinson Microwave Anisotropy Probe suggested the existence of an ‘axis of evil’, but that was later been disputed as a random fluke.

In the latest study cosmologists have been studying the oldest cosmic radiation - the afterglow of the Big Bang - for indications of what the universe is up to.

From their work the scientists have been able to conclude what the Cosmological Principle had long predicted - that the universe has no preferred direction of expansion and is the same everywhere.

It is moving in every way at exactly the same rate, there is no spin axis or special direction in space.

Lead author Daniela Saadeh, explained to Universe Today: “We analysed the temperature and polarisation of the cosmic microwave background [CMB]...using data from the Planck mission. We compared the real CMB against our predictions for what it would look like in an anisotropic universe.

“After this search, we concluded that there is no evidence for these patterns and that the assumption that the Universe is isotropic on large scales is a good one.”

In fact, they are so certain they claim that there is only a 1 in 121,000 chance that a preferred direction of expansion actually exists.

Which, while useless for our own sense of place, is great news for cosmologists’ standard model of universal evolution, which has long rested on the assumption of such uniformity.